Below is what you need to set your BF3 server to for hardcore mode. Please reference the BF3 Server Admin Documentation for further information.
[bash]vars.autoBalance true
vars.friendlyFire true
vars.regenerateHealth false
vars.killCam false
vars.miniMap true
vars.hud false
vars.3dSpotting false
vars.miniMapSpotting true
vars.nameTag false
vars.3pCam false
vars.vehicleSpawnAllowed true
vars.soldierHealth 60
vars.onlySquadLeaderSpawn true[/bash]
